Drop-out fuse device



March 20, 1945. w o SCHULTZ 2,372,126

DROP OUT FUSE DEVICE Filed Sept. 22, 1941 4Sheets-Sheet l INVENTOR.Mum/14 O Jam/z rz A TTORNE March 20, 1945. w, o, scHuLTz DROP-OUT FUSEDEVICE 4 Sheets-Sheet 2 Filed Sept. 22, 1941 m &u M M E 0 N M March1945. w. o. SCHULTZ 2,372,126

DROP-OUT FUSE DEVICE Filed Sept. 22, 1941 4 Sheets-Sheet 3 1] I 11 5 I I76 1 75 INVENTOR.

f9 zz/AM 0. Jc/Mrz March 20, 1945. w. o. SCHULTZ DROP-OUT FUSE DEVICE 4Sheets-Sheet 4 Filed Sept. 22, 1941 INVENTOR. W/lZ/AM 0. \Sc/a/zrz ATOEY.

Patented Mar. 20, 1945 DROP-OUT FUSE DEVICE- William 0. Schultz, SouthMilwaukee, Wis., assignor to Line Material Company, South Milwaukee,Wis., a corporation of Delaware Application September 22, 1941, SerialNo. 411,812

21 Claims.

This invention relates to a drop-out fuse device.

Objects of this invention are to provide a novel form of fuse,preferably a housed type of expulsion fuse for example, in which thefuse tube is biased downwardly and is slidably guided and is normallyrestrained from such motion by the fuse link, but which upon blowing ofthe fuse link first acts in the manner of an expulsion fuse andthereafter moves downwardly and projects from the lower portion of thehousing, thus increasing the gap in the circuit as the upper contact ofthe fuse tube moves away from the upper stationary contact carried bythe housing.

Further objects are to provide a construction in which the lowerfastening means or retaining lever for the fuse link is carried by thefuse tube itself and moves downwardly with the fuse tube when it isreleased by the rupturing of the fuse link, such lower retaining leverbeing biasedtoward outward motion and withdrawing any of the lowerportion of the fuse link that may remain intact from the fuse tube in aquick and positive manner and also detaching itself from a stationarypart of the device to which it was originally releasably attached.

Further objects of this invention are to provide a drop-out fuseconstruction in which the. lower retaining member or lever which iscarried by the fuse tube is electrically dead after the fuse blows andso that thereby any portion of the fuse link hanging therefrom is alsoelectrically dead, thereby guarding against accidental hazards and yetgiving a visual indication by the projecting portion of the fuse tubeand associated parts that the fuse link has been ruptured.

Further objects are to provide a drop-out fuse construction in whichmain upper contact means are provided which include both a contactcarried by the fuse tube and spaced downwardly from the upper endthereof and a stationary contact which carry the main current undernormal conditions. and thus locate what is sometimes called the hot spotat a point remote from the upper closure cap which clamps the upper endof the fuse link, latch means being also provided to hold the fuse tubein closed position and also to maintain contact during a portion of thedownward sliding motion of the fuse tube, both the main contact membersand the latch means urging the fuse tube downwardly in addition to theeffect of gravity.

' Further objects are to provide a drop-out fuse construction in which ahousing is provided with a pivotal door which carries a sleeve throughwhich the fuse tube slides, a barrier being also carried from the doorand preferably integral with the sleeve and extending substantiallyacross the lower portion of the channel-shaped housing, t therebyseparate the lower end of the fuse link and the open projecting end ofthe fuse tube and the fuse link extractor or retaining lever from allother portions of the apparatus, to there- 1 by prevent the entrance ofgases upon the blowing of a fuse link from the main body of the housing,the barrier being spaced upwardly from the lower end of the housing andfrom the lower end of the door to provide a shelter for the lower end ofthe fuse tube, the retaining lever or fuse link extractor, and for thelower end of the fuse link under normal conditions.

In general this invention is an improvement over that disclosed inPatent No. 2,138,255 of November 29, 1938, for Fuse construction, issuedto William O. Schultz and Alwin G. Steinmayer.

Embodiments of the invention are shown in the accompanying drawings, inwhich:

Figure l is a side elevation, partly in section, showing the fuse devicein its operative position.

Figure 2 is a view from the bottom of Figure 1.

Figure 3 is a view with the door removed and with parts in section andbroken away.

Figure 4 is a view looking down from the top of the device with the topof the housing broken away.

Figure 5 is a sectional of Figure 1.

Figure 6 is a sectional view on the line 6-6 of Figure 1.

Figure 7 is an enlarged fragmentary view, partly in section, showing thedevice as it appears when the releasing lever or fuse link extractor hasmoved part way towards releasing position uponrupture of the fuse link.

Figure 8 is a view looking into the housing from the front showing theupper end of the device with the door removed.

Figure 9 is a view, partly in section, showing the position of the partsafter the fuse link has slid downwardly to its lowermost position.

Figure 10 is a fragmentary view of a further view on the line 5-5 formof the invention.

Referring to the drawings, it will be seen that the device comprises achannel-shaped housing I formed of insulating material and having anopen front and an open lower end. This housing is normally closed by aninsulating door 2. This door is provided with a metal guiding sleevespaced a distance from the lower end thereof. This barrier is providedwith a pair of downwardly extending lugs which carry a pivot pin 6. Thepivot pin is received Within a pair of hook members 1 which are cementedor otherwise secured in the rear wall of the housing.

The housing is also provided with an upper and a lower resilientstationary contact indicated at 8 and 9 respectively. The lowerstationary contact 9 is provided with inwardly turned outwardly flaringend portions I0, see Figure 6, so that they will hook over the sides ofthe sleeve 3 and thus hold the door closed whether the fuse is in itsuppermost or in its lowermost position, as will hereinafter bedescribed.

The upper contact 8 is provided with a pair of resilient arms which haveoutwardly turned lower ends H. The lower and upper contact are carried,respectively, by vertical plate like members is and it which haverearward extensions ce merited or otherwise secured in the rear wall orthe housing. These members are apertured and receive a pair of screws l5which are threaded into conductor clamping plates I6 so that the lineand load conductors leading through the apertures in the side walls ofthe housing may be clamped between the rear plates l6 and the forwardplates l3 and M at any angle desired.

The up er plate M of the upper terminal structure also carries. aU-shaped resilient latch H which has downwardly slanting inner faces andwhich has inwardly turned and outwardly flaring end portions l8, seeFigure 4.

An insulating fuse tube I9 is slid-ably mounted within the sleeve 3 andis provided with an upper closul'e cap 2B of metal which clamps theupper buttonhead 2i of the fuselink. The fuse link is provided with astrain wire 22 and a fusible section 23 and a flexible leader 24. Thisfuse link is carried within the fuse tube and projects outwardly throughthe open lower end thereof.

The fuse tube is also provided with an upper contact which is indicatedgenerally at 25 and is provided with a pair of upwardly. slantingcontact surfaces 26 on opposite sides thereof which engage the outwardlyturned portions H of the upper resilient stationary contact 8, seeFigure 3.

The upper closure cap is normally engaged and held by the upperresilient latch H, as shown in Figures 1, 3 and 4. It is to be notedthat the upper stationary resilient contact 8 has a cam action with theslanting faces 26 of the upper contact of the fuse tube and urges thefuse tube downwardly. In addition to this, it is to be noted that theupper resilient latch l7 urges the fuse tube downwardly. These twoforces are in addition to the action of gravity which also urges thefuse tube downwardly.

If desired the do'or'2 maybe provided with an inwardly projecting finger.25", see Figures 1 and 5, which fits withinja recessed portion of theupper contact of the fuse tube so that when the door is moved towardsdosed position, excessive strain is not placed on the sleeve 3 butinstead the upper end of the fuse tube is pushed into place by thefinger 25 of the door 2. Also it is to be noted, particularly fromFigures 1 and 5, that the rear faces of the outwardly projectingportions of the upper contact 25 are "slanting so as to facilitatespreading of the arms of the ppe'r resilient contact 8 when the fusetube is rocked into closed position.

The fuse tube is provided with a collar 21 adjacent and spaced from-itslower end. This collar is provided with a rearwardly projecting rigidarm 28 to which is pivotally mounted the fuse link extracting lever 29.This fuse link extracting lever is also the means for holding the fusetube in its uppermost position as long as the fuse link is unrupturedand for releasing the fuse tube upon rupture ofv the fuse link whilealso acting as a fuse link extractor.

, The fuse link extractor 29, it will be seen from Figures 1, 7 and 9,is pivoted intermediate its ends to the lower end of the arm 23 rigidwith the collar 21 carried by the fuse tube l9. Its

rear end is hook-shaped as indicated at 30 and normally hooks over thepivot pin 6. The fuse link extractor extends forwardly and is spaced tothe side of one side of the fuse tube, the fuse tube being preferablyprovided with a flat face 3|, see Figures 3 and 9, adjacent the fuselink extractor.

This fuse link extractor is provided with a fuse I linkiclamping thumbscrew 32 which is threaded on a stud 33 carried by the fuse linkextractor 29 and which serves to clamp the leader 24 of the fuse link,as shown in Figures 2 and 3. This fuse link extractor 2!; is providedwith a notched lower portion 3 3 within which the transversely bentportion of the fuse link is positioned and it is also provided with alaterally projecting boss 35 behind which the extreme end of the leader24 of the fuse link is positioned, as shown most clearly in Figures 1and 3.

When the fuse link is intact and the door 2 is rocked to closedposition, the upper latch engages the upper closure cap 20 of the fusetube and the upper resilient stationary contact 8 has its arms slightlysprung apart and engages the slantin contact surfaces 26 of the uppercontact 25 of the fuse tube, see Figure 3, and the arms of the lowerresilient stationary contact 9 engage the flat opposed contact faces 36formed on the sleeve 3, as shown most clearly in Figure 6, the inwardlyturned ends l0 hooking in front of the outwardly projecting lateralportions of the sleeve 3.

It is to be noted that the upper resilient stationary contact 8 has arelatively high bearing pressure against the contact surfaces 26 of theupper contact 26 of the fuse tube and thus what is usually termed thehot spot is removed from the upper closure cap of the fuse tube. Thoughthe upper closure cap of the fuse tube is metal and contacts with theresilient metal arms ll of the latch, nevertheless the major currentflow passes through the main upper contact members 25 and 8, see Figure3, and relatively small current passes from the closure cap 20 to thelatch arm's .l'i. It may be desirable, as has been shown in the drawing,to provide a laminated structure for the upper and lower resilientstationary contacts 8 and 9. The inner arms of these contacts may bemost highly conducting and the outer arms may be more resilient andassist in furnishing the spring pressure to insure adequate contact, or,if desired, both of the members forming the laminated structure in eachof the upper and lower stationary contacts may be of the same materiaL-a When an overload occurs and the fuse link is ruptured, the fuse tubeis released and moves downwardly as the combined fuse link extractor andfuse tube retaining member '29 rocks about its intermediate pivot point31, see Figures 1 and 7, "and the hook like portion 30 of the fuse linkextractor moves away from the pivot pin 6 and thus completely releasesthe fuse tube. The fuse tube moves downwardly and carries with it thefuse link extractor so that the fuse link extractor, as well as anyremaining unburned portion of the fuse link, are electrically dead afterrupture of the fuse link and after the fuse tube has moved to itslowermost position, as shown in Figure 9.

It is to be noted that the resilient upper stationary contact 8maintains contact with the upper contact of the fuse tube for a briefinterval during the downward sliding motion and the upper resilientlatch arms I! maintain contact with the closure cap for a longer periodduring the downward sliding motion of the fuse tube to thereby insurecomplete rupture of the circuit within the fuse tube prior to thebreaking of contact between the upper end of the fuse tube and the upperterminal.

The door remains closed after the fuse tube has slid downwardly to itslowermost position, as shown in Figure 9, due to the interengagementbetween the lowerstationary contact 9 and the sleeve 3, as shown mostclearly in Figure 6.

In the form of the invention shown in Figure 10, a slightly differentmanner of securing the cam action between the resilient stationary uppercontacts and the upper main contact of the fuse tube is provided. Thisis secured by having the upper stationary resilient contact 39 providedwith flat upwardly slanting arms which engage protuberences 40 extendingoutwardly from opposite sides of the main upper contact 4! of the fusetube. It is apparent that a cam action is obtained by this constructionwhich acts to produce a downward thrust on the fuse tube.

It will be seen that a novel form of drop-out fuse device has beenprovided in which the relatively hot'spot is removed from the closurecap, and it will be seen further that the construction is such that atransverse barrier carried rigidly by the door and preferably integralwith the sleeve has been provided which extends transversely across thechannel-shaped housing and serves to divide the housing off below thelower stationary contact so that the fuse link extractor, the open endof the fuse tube, and the lower end of the fuse link are all locatedbelow the barmen In this way there is very little chance of anyconducting gases flashing back into the body of the housing. If desired,this effect may be some what enhanced by providing a transverseconnecting web 38 which joins the hook like members 1 and which extendstransversely across slightly above the inner end of the barrier 4, asshown most clearly in Figure 2.

By having the barrier spaced upwardly a slight distance from the lowerend of the channelshaped housing, it will be seen from Figures 1 and 3particularly, that a small individual compartment is provided for thefuse link extractor so that it is sheltered from snow and rain butnevertheless is separated on from the lower stationary contact or anyother interior portion of the housing above the barrier.

In refusing the device, the fuse tube and door assembly may be unhookedfrom the hook memher 1 and the fuse tube may be refused and thereafterthe assembly may be again pivotally connected to the hooks 1 and thedoor and fuse tube assembly rocked back to closed position.

Although this invention has been described in considerable detail, it isto be understood that such description is intended as illustrativerather than limiting, as the invention may be variously embodied and isto be interpreted as claimed.

I claim:

1. A drop-out fuse device having upper and lower stationary contacts, adownwardly biased fuse tube, guiding means for slidably guiding saidfuse tube, a contact rigidly carried by said fuse tube adjacent theupper end thereof and having a slanting surface normally engaging theupper stationary contact, said upper stationary contact being resilientand producing a downward thrust on said fuse tube through the agency ofthe slanting surface of the contact of said fuse tube, said slantingsurface acting like a cam and said resilient upper contact exerting alateral pressure on said slanting surface, a fuse link within said fusetube, means adjacent the upper end of said fuse tube and spaced from thecontact of said fuse tube and separate and distinct from the contact ofsaid fuse tube for locking the upper end of said fuse link, and meanscontrolled by said fuse link and normally holding said fuse tube in itsuppermost position and releasing said fuse tube upon rupture of saidfuse link.

2. A drop-out'fuse device having upper and lower stationary contacts, adownwardly biased fuse tube mounted for both downward and lateralmotion, guiding means for slidably guiding said fuse tube, a contactcarried by said fuse tube adjacent the upper end thereof and having aslanting surface normally engaging the upper stationary contact, saidupper stationary contact being resilient and producing a downward thruston said fuse tube through the agency of the slanting surface of thecontact of said fuse tube, said slanting surface acting like a cam andsaid resilient upper contact exerting a lateral pressure on saidslanting surface, a fuse link within said fuse tube, and a stationarylatch distinct from said upper stationary contact for locking said fusetube in place against lateral motion, and a fuse link extractor biasedtowards fuse link extracting motion and controlled by said fuse link andnormally holding said fuse tube in its uppermost position and releasingsaid fuse tube upon rupture of said fuse link, said fuse link extractorbeing electrically dead when said fuse tube has slid downwardly.

3. A drop-out fuse device having upper and lower stationary contacts, adownwardly biased fuse tube mounted for both downward and lateralmotion, guiding means for slidably guiding said fuse tube, a contactcarried by said fuse tube adjacent the upper end thereof and cooperatingwith said upper stationary contact to form a pair of contactingelements, one of said contacting elements having a slanting surface andthe upper stationary contact being resilient to produce a downwardthrust on said fuse tube through the agency of said slanting surface, astationary latch distinct from said upper stationary contact for holdingsaid fuse tube against lateral motion, a fuse link within said fusetube, the said slanting surface being engaged by the other contact andhaving a cam action to produce said thrust, and a fuse link extractorbiased towards fuse link extracting motion and controlled by said fuselink and normally holding said fuse tube in its uppermost position andreleasing said fuse tube upon rupture of said fuse link, said fuse linkextractor being electrically dead when said fuse tube has sliddownwardly.

4. A drop-out fuse device having upper and lower stationary contacts, adownwardly biased fuse tube mounted for both downward and lateralmotion, guiding means for slidably guiding said'fuse tube, a contactcarried by said fuse tube adjacent the upper end thereof and havingupwardly slanting surfaces on opposite sides thereof, said upperstationary contact being resilient and having contact surfaces normallyengaging the slanting surfaces of the contact of said fuse tube andbeing spread apart by the contact of said fuse tube and cooperating withsaid slanting surfaces to produce a cam action urging said fuse tubedownwardly, a fuse link within said fuse tube normally electricallyconnecting the contact of said fuse tube and said lower stationarycontact, a stationary latch distinct from said upper stationary contactfor holding said fuse tube against lateral motion, and means controlledby said fuse link for normally holding said fuse tube in its uppermostposition and releasing said fuse tube for downward sliding motion uponrupture of said fuse link, the means controlled by said fuse link beingelectrically dead when said fuse tube has slid downwardly.

5. A drop-out fuse device having upper and lower stationary contacts, adownwardly biased fuse tube, guiding means for slidably guiding saidfuse tube,-a contact rigidly carried by said fuse tube adjacent andspaced from the upper end thereof and having contact surfaces onopposite sides thereof, said upper stationary contact being resilientand having arms engaging the contact surfaces of the contact of saidfuse tube and having a cam action therewith to produce a downward thruston said fuse tube, a fuse link within said fuse tube normallyelectrically connecting the contact of said fuse tube and said lowerstationary contact, a closure cap for clamping the upper end of saidfuse link to the upper end of said fuse tube in spaced relation to thecontact carried by the fuse tube, and means controlled by said fuse linkfor normally holding said fuse tube in its uppermost position andreleasing said fuse tube for downward sliding motion upon rupture ofsaid fuse link, all portions of said tube and closure cap movingdownwardly as a unit upon rupture of said fuse link, the meanscontrolled by said fuse link being electrically dead when said fuse tubehas slid downwardly,

6. A drop-out fuse device having upper and lower stationary contacts, adownwardly biased fuse tube mounted for both downward and lateralmotion, guiding means for slidably guiding said fuse tube, a contactcarried by said fuse tube adjacent the upper end thereof and havingupwardly slanting surfaces on opposite sides thereof, said upperstationary contact being resilient and having contact surfaces normallyengaging the slanting surfaces of the contact of said fuse tube andbeing spread apart by the contact of said fuse tube and cooperating withsaid slanting surfaces to produce a cam action urging said fuse tubedownwardly, a fuse link within said fuse tube normally electricallyconnecting the contact of said fuse tube and said lower stationarycontact, a stationary latch distinct from said upper stationary contactfor holding said fuse tube against lateral motion, and a fuse linkextractor biased towards fuse link extracting motion by said fuse tubecontrolled by said fuse link for normally holding said fuse tube in itsuppermost position and releasing said fuse tube for downward slidingmotion upon rupture of said fuse link, said fuse link extractor beingelectrically dead when said fuse tube has slid downwardly.

'7. A drop-out fuse device having upper and lower stationary contacts, adownwardly biased fuse tube having an open lower end and having a metalclosure cap at its upper end and having a contact adjacent its upper endspaced downwardly from said closure cap, the contact of said fuse tubehaving slanting faces, said upper stationary contact being resilient andhaving spaced arms normally engaging the slanting faces of the contactof said fuse tube and cooperating with said slanting faces to produce adownward thrust on said fuse tube, guiding means for slidably guidingsaid fuse tube, a fuse link within said fuse tube normally electricallyconnecting said upper and lower stationary contacts and having its upperend clamped by said closure cap and having its lower end projecting fromthe open end of said fuse tube, and means controlled by said fuse linkand normally holding said fuse tube in its uppermost position andreleasing said fuse tube upon rupture of said fuse link.

8. A drop-out fuse device having upper and lower stationary contacts, adownwardly biased fuse tube having an open lower end and havin a metalclosure cap at its upper end and having a contact rigidly oarriedby saidfuse tube adjacent its upper end spaced downwardly from said closurecap, the contact of said fuse tube having slanting faces, said upperstationary contact being resilient and having spaced arms normallyengaging the slanting faces of the contact of said fuse tube andcooperating with said slanting faces to produce a downward thrust onsaid fuse tube by means of a cam action with said slanting faces,guiding means for slidably guiding said fuse tube, a fuse link withinsaid fuse tube normally electrically connecting said upper. and lowerstationary contacts and having its upper end clamped by said closure capand having its lower end projecting from the open end of said fuse tube,saidclosure cap locking the upper portion of said fuse link to the upperportion of said fuse tube in spaced relation to the contact carried bythe fuse tube, and a fuse link extractor biased towards fuse linkextracting motion and controlled by said fuse link and normally holdingsaid fuse tube in' its uppermost position and releasing said fuse tubeupon rupture of said fuse link.

9. A drop-out fuse device having upper and lower stationary contacts, adownwardly biased fuse tube having an open lower end and having a metalclosure cap at its upper end and having a contact adjacent its upper endspaced downwardly from said closure cap, said upper stationary contactbeing resilient and having spaced arms normally engaging the contact ofsaid fuse tube and cooperating with said contact of said fuse tube toproduce a downward thrust on said fuse tube, guiding means for slidablyguidingsaid fuse tube, a fuse link within said fuse tube normallyelectrically co inecting said upper and lower stationary contacts andhaving its upper end clamped by said closure cap and having its lowerend projecting from the open end of said fuse tube, means controlled bysaid. fuse link and normally holding said fuse tube in its uppermostposition and releasing said fuse tube upon rupture of Said fuse link,said guiding means being pivotally mounted, and a latch distinct fromsaid upper stationary contact normally engaging the closure cap of saidfuse tube.

10. A drop-out fuse device comprising a fuse tube, pivotally mountedguiding means slidably guiding said fuse tube, said fuse tube having anupper contact spaced downwardly from its upper end and having an upperclosure cap and having an open lower end, a fuse link within said fusetube having its upper end clamped by said closure cap and projectingoutwardly from the open lower end of said fuse tube, an upper and alower stationary contact normally electrically joined by said fuse link,said upper contact engaging the normally holding said fuse tube in itsuppermost position and releasing said fuse tube upon rupture of saidfuse link for downward sliding of said fuse tube.

contact carried by said fuse tube and cooperating with said contact oflink for normally holding said fuse tube in its uppermost position andreleasing said fuse tube for downward sliding motion upon rupture ofsaid fuse link, and a latch ried by said housing of said fuse tube.

12. A housed type of drop-out fuse device including a housing, a sleevepivotally mounted on said housing, a door carried by said sleeve, a fusetube slidably mounted within said sleeve and having an closure cap, saidhousing having an upper and a lower stationary contact, said upperstationary contact normally engaging the contact of said fuse tube, afuse link within said fuse tube having its upper end clamped by saidclosure cap and projecting outwardly fro-m the open lower end of saidfuse tube and normall electrically connecting said stationary contacts,a latch distinct from said upper by the housing for engaging the closurecap of said fuse tube, said latch being resilient and urging said fusetube downwardly, and means controlled by said fuse link for normallyholding said fuse tube in its uppermost position, said means releasingsaid fuse tube for downward sliding motion upon rupture of said fuselink.

13. A housed type of drop-out fuse device including a housing, a sleevepivotally mounted on said housing, a door carried by said sleeve, a fusetube slidably mounted within said sleeve and having an open lower endand having a closure cap closing its upper end, said fuse tube having anupper contact located below said closure cap, a fuse link within saidfuse tube having its upper and clamped by said closure cap andprojecting outwardly from the open lower end of said fuse tube, saidhousing having an upper and a lower stationary contact normallyelectrically connected by said fuse link, said upper contact beingresilistationary contact carried ent and engagingthe upper contactcarried by said fuse tube and cooperating with said contact of said fusetube to provide a downward thrust for said fuse tube, means controlledby said fuse link for normally holding said fuse tube in its uppermostposition and releasing said fuse tube for downward sliding motion uponrupture of said fuse link, and a latch distinct from said upperstationary contact carried by said housing for engaging the closure capof said fuse tube, said latch exerting a downward pressure on said fusetube.

14. A housed type of drop-out fuse device in cluding a housing, a sleevepivotally mounted on said housing, a door carried by said sleeve, a fusetube slidably mounted within said sleeve and having an open lower endand having a closure cap closing its upper end, said fuse tube havingbelow said closure cap, having its upper end clamped by said closure capand projecting outwardly from the open lower end of said fusetube, saidhousing having an upper and a lower stationary contact normallyelectrically connectthrust for said fuse tube, means controlled b saidfuse link for normally holding said ruse tube in its uppermost position,and a latch distinct from said through the agency of said slantingsurfaces by of said fuse tube, a stationary latch distinct from saidupper stationary contact for engaging the upper portion of said fusetube and holding said fuse tube against lateral motion, and a fuse linkextractor pivoted intermediate its ends to said fuse tube and having oneend detachably engaging supporting means rigid with said guiding meansand having the other end secured to the projecting portion of said fuselink, said fuse link extractor normally holding said fuse tube in itsuppermost position and releasing said fuse tube upon rupture of saidfuse link and detaching means and being fuse tube has slid downwardly.

16. A drop-out fuse device having upper and lower stationary contacts, adownwardly biased fuse tube, guiding means for slidably guiding saidfuse tube, a contact carried by said fuse tube normally engaging theupper stationary contact and movable away from the upper stationarycontact When said fuse tube slides downwardly, a fuse link within saidfuse tube normally electrically connecting the contact carried by thefuse tube with the lower stationary contact, a barrier wardly with saidfuse tube fuse tube, a contact carried by said fuse tubethe upperstationary contact and movable away from the upper stationary contactwhen said fuse tube slides downwardly, a fuse link within said fuse tubenormally electrically connecting the contact carried by the fuse tubewith the lower stationary contact, a barrier rigid with said guidingmeans and extending transversely of said fuse tube, said fuse tubenormally projecting below said barrier and slidable downwardly throughsaid barrier, and releasing means normally holding said fuse tube in itsuppermost position, said releasing means being located below saidbarrier and being controlled, by said fuse link, said releasing meansbeing carried by said fuse tube and moving down normally engaging slidesdownwardly upon rupture of said fuse link and being electrically deadwhen said fuse tube has slid downwardly.

18. A housed type of drop-out fuse device including a housing and a doorpivotally mounted on said housing, saidhousing having upper and lowerstationary contacts, a barrier carried by said door and extendingtransversely of said housing adjacent the lower end of said housing, afuse tube carried by said door and slidable through said housing andbeing downwardly biased, a fuse link within said fuse tube normallyelectrically connecting said stationary contacts, and a fuse linkextractor carried by said fuse tube and located below said barrier andcontrolled by said fuse link, said fuse link extractor normally holdingsaid fuse tube in its uppermost when said fuse tube V position andreleasing said fuse tube upon rupture of said fuse link.

19. A housed type of eluding a channel-shaped housing having an openfront and an open lower end, upper and lower stationary contacts locatedwithin said housing, a door pivotally mounted on said housing andnormally closing the front of said housing, said door having a barrierrigid therewith and located within and extending transversely across thechannel-shaped housing above the lower end of said housing, a downwardlybiased fuse tube slidable through said barrier, a fuse link within saidfuse tube normally electrically connecting said stationary contacts,said fuse tube having a closed upper end and having an open lower endprojecting below said barrierwhen'said fuse tube is in its uppermostposition,

drop-out fuse device inlower end projecting and a fuse link extractingmember carried by the lower portion of said fuse tube and located belowsaid barrier and controlled by said fuse link, said fuse link extractingmember normally holding said fuse tube in its uppermost position andreleasing said fuse tube upon rupture of said fuse link and movingdownwardly with said fuse tube when said fuse tube slides downwardly andbeing electrically dead when said fuse tube has slid downwardly uponrupture of said fuse link.

20. A housed type of drop-out fuse device including a channel-shapedhousing having an open front and an open lower end, upper and lowerstationary contacts located within said housing, a door pivotallymounted on said housing and normally closing the front of said housing,said door having a barrier rigid therewith and located within andextending transversely across the channel-shaped housing above the lowerend of said housing, a downwardly biased fuse tube slidable through saidbarrier, a fuse link within said fuse tube normally electricallyconnecting said stationary contactssaid fuse tube having a closed upperend and having an open below said barrier when said fuse tube is in itsuppermost position, and a fuse link extracting member carried by thelower portion of said fusetube and located below said barrier andcontrolled by said fuse link, said barrier being located between saidfuse link extracting member and the lower stationary contact, said fuselink extracting member normally holding said fuse tube in its uppermostposition and re leasing said fuse tube upon rupture of said fuse linkand moving downwardly with said fuse tube when said fuse tube slideselectrically dead when said fuse tube has slid downwardly upon ruptureof said fuse link.

21. A drop-out fuse device having upper and lower stationary contacts, adownwardly biased fuse tube mounted for both downward sliding andlateral motion, guiding means for slidaloly guiding said fuse tube, acontact carried by said fuse tube adjacent the upper end thereof andcooperating with said upper stationary contact, said upper stationarycontact being resilient and having slanting contacting surfaces engagingthe contact of said fuse tube and producing a downward thrust on saidfuse tube due to the cam action between said slanting faces and thecontact of said fuse tube, a stationary latch distinct from said upperstationary contact for engaging the upper portion of said fuse tube andholding said fuse tube against lateral motion, and a fuse link extractorbiased towards fuse link extracting motion and controlled by said fuselink and nor mally holding said fuse tube in its uppermost position andreleasing said fuse tube upon rupture of said fuse link, said fuse linkextractor being electrically dead when said fuse tube has sliddownwardly.

WILLIAM O. SCHULTZ.

downwardly and being

